NEC Network Controller uPD98502 - Manual (Page 114)

CHAPTER 2 V R 4120A
114 Preliminary User’s Manual S15543EJ1V0UM
(7) xksseg (64-bit kernel mode, current supervisor space)
When KX = 1 in the Status register and bits 63 and 62 of the virtual address space are 01, the xksseg address
space is selected; it is the 1-Tbyte (2
40
bytes) current supervisor address space. The virtual address is extended
with the contents of the 8-bit ASID field to form a unique virtual address.
(8) xkphys (64-bit kernel mode, physical spaces)
When the KX = 1 in the Status register and bits 63 and 62 of the virtual address space are 10, the virtual address
space is called xkphys and selected as either cached or uncached. If any of bits 58 to 32 of the address is 1, an
attempt to access that address results in an address error.
Table 2-31. Cacheability and xkphys Address Space
Bits 61-59 Cacheability Start Address
0 Cached 8000_0000_0000_0000H
to
8000_0000_FFFF_FFFFH
1 Cached 8800_0000_0000_0000H
to
8800_0000_FFFF_FFFFH
2 Uncached 9000_0000_0000_0000H
to
9000_0000_FFFF_FFFFH
3 Cached 9800_0000_0000_0000H
to
9800_0000_FFFF_FFFFH
4 Cached A000_0000_0000_0000H
to
A000_0000_FFFF_FFFFH
5 Cached A800_0000_0000_0000H
to
A800_0000_FFFF_FFFFH
6 Cached B000_0000_0000_0000H
to
B000_0000_FFFF_FFFFH
7 Cached B800_0000_0000_0000H
to
B800_0000_FFFF_FFFFH